Method of and device for processing fibrous material

ABSTRACT

Method of and apparatus for processing fibrous material to yarn by cooperation of an electrostatic field. Fibers are caught after opening, are parallelized on a doubling means by the action of an electrostatic field and are continuously withdrawn therefrom by a rotating free end of yarn. The rotation of the free end of yarn is exerted by a twisting means acting upon the yarn to be formed beyond the zone of connection of the fibers to the rotating end of yarn.

United States Patent Safar Aug. 26, 1975 [54] METHOD OF AND DEVICE FOR141L284 11/1968 Corbaz ct a1 57/5891 PROCESSING FIBROUS MATERIAL3,537,249 11/1970 Mayer v r i A .1 57/5889 3,552.112 1/1971 Chabot i57/58.89 X

[75] In en r: Vaclav f Llberec, 3,665 695 5/1972 Amato r a r 57/5391Czechoslovakia 16961300 10/1972 Mayer ct al 1 1 1 4 .1 57/5889 3,696,60310/1972 Kotter et a1 r v 4 v 1 A 4. 57/5889 [73] Asslgnee: T zamdy3,761148 10/1973 'nirower .r 57 34 R x strojirenstvi, generalnireditelstvi, Liberec, Czechoslovakia Primary Examiner-Donald E, Watkins[22] Filed: June 5, 1974 [21] Appl. No.: 476,471

{57] ABSTRACT [30] Foreign Application Priority Data Method of andapparatus for processing fibrous mate- June 7 1973 Czechoslovakia4100.73 rial to yarn by cooperation of an electrostatic field. Fi-

. bers are caught after opening, are parallelized on a [52] US. Cl57/5839; 57/5895 doubling means by the action of an electrostatic field[51 1 Int. Cl DOlh 1/12 and are continuously withdrawn therefrom by arotat- {58] Field of Searchmm 57/5, 6, 34 R, 58159-5895, ing free end ofyarn. The rotation of the free end of 57/773, 156 yarn is exerted by atwisting means acting upon the yarn to be formed beyond the zone ofconnection of [56] References Cited the fibers to the rotating end ofyarn UNITED STATES PATENTS 23 Claims, 6 Drawing Figures 1107,472410/1963 Arshmov et a1. 57/7753 X PATENTEI] M182 6 I975 SHIT E OF 4PATENTEUAUBZBWB 2.90 1.012

METHOD OF AND DEVICE FOR PROCESSING FIBROUS MATERIAL The presentinvention relates to a method of and a device for processing fibrousmaterial to yarn by the action of static electricity.

Many prior methods of processing fibrous material to yarn are known. Themost important feature, according to which the different prior methodsare distinguished, consists in the manner of reinforcing the silver offi brous material formed by a certain linear sequence of fibers mutuallyconnected in said silver. Several methods hitherto known use adhesivemeans by means of which the fibers in the silver are mutually linked,whereby their coherence and the strength of the fibrous silver thusformed are secured. The adhesive means might be removed later, e.g. bywashing, or it becomes a permanent component of the yarn forming thefinal product of the fibrous body. In other methods, using this kind ofreinforcing of fibrous material, a component formed of thermoplasticfibers is used, by means of which cohesion of a further component orcomponents into yarn as a final product of fiber processing is achievedupon plastifying said thermoplastic fibers. Those yarns have certainspecific properties and fields of application corresponding thereto. Acertain disadvantage of yarns thus produced consists in their relativecostliness caused by using adhesive means and by the intricacy of itsmanufacturing device employed.

The most widespread method of reinforcing a silver of fibrous materialhitherto known consists in reinforcing the sliver by twisting, which maybe performed in various manners. Twist is imparted to the yarn either byrotating a yarn winding, as e.g. upon conventional ring spinning (in aring'traveller system), or by rotation of an open end of yarn beingformed, or possible by alternating twisting a fibrous sliver in bothdirections, whereupon a so-called false twist is formed, in whichregular alternation of yarns with left and right twist direction isobtained. Between those sections, a certain twistless section isencountered, whereby the final product i.e. the yarn is disturbed as toits appearance and as well from the viewpoint of its properties,particularly its strength. The twisting of an open yarn end is performedin certain cases in a purely mechanical manner, including joining fibersto the rotating fibrous silver, which is withdrawn, upon twisting,through the axis of the rotary body. In the pneumomechanical method, arotary spinning chamber is particularly used, into which there are fedfibers separately by means of an air stress exerted by underpressure(partial vacuum) in said spinning chamber, and deposited about thecircumference thereof in the form of a ribbon in a different sequencefrom that existing before in the fibrous material to be processed. Thefibers deposited in the ribbon inside the spinning chamber arecontinuously withdrawn after being joined to and twisted about the openyarn end and withdrawn through the axis of rotation of the spinningchamber in the form of yarn. Further methods are known, in which theopen yarn end is twisted by means of a turbulent processing fluid,mostly an air vortex, or possibly a rotating electrostatic field.

The disadvantage of the known manufacturing method of yarn in a rotaryspinning chamber consists particularly in its limited output; this iscaused by centrifugal forces acting upon the yarn upon its withdrawalfrom the collecting surface in view of the fact that the diameter of thespinning chamber is chosen with a certain relation to the length of thefibers to be spun. In this method, a further disadvantage is encounteredwhich consists in the reduced strength of the yarn produced in therotary spinning chamber.

In methods using a turbulent processing fluid for twisting, both thereduced strength of yarn as well as its unevenness which causes anunattractive appearance thereof, are serious disadvantages.

The so-called electrostatic method of spinning, i.e. twisting fibers inan electrostatic field, is hitherto known in several modifications.According to one modification of that method, the fibers are fed in aseparated condition transversely to the spot electrode and arestraightened thereupon by another field formed by the twisting spindle.

According to another modification of this spinning method, the fibersare fed in separated condition through an electrode in the forth of atube in the direction of its axis to a twisting spindle forming theother electrode.

The common feature of those two modifications of the hitherto knownelectrostatic spinning method consists in straightening fibers betweenthe twisting spindle forming one electrode or pole, and the otherelectrode or pole. The fibers are spun into the yarn in the samesequence as they are fed from the fiber separating element, and the flowof fibers is not interrupted between the open rotating yarn end and theseparating element, i.e. the fibers move even during their straighteningfrom the fiber separating element to the twisting electrospindle. Due tothat, the sequence of fibers cannot be intentionally changed.

The common disadvantage of the above modifications of the electrostaticspinning methods consist in the inconsistency of the different actionsof both the electrostatic and mechanical forces simultaneously actingupon the fiber upon spinning it into yarn. The joining of fibers in thismethod is to be performed in separated condition, i.e. upon separatingthe fibrous material to separate fibers. Otherwise, it would not bepossible efficiently to straighten the fibers in the electrostaticfield. Due to the required speed of spinning, a high voltage value isnecessarily applied in the electrostatic field of this method, due tothe speed of the fiber flow fed to the yarn twisting point, However, theaction of the electrostatic forces upon the fibers is very short, andthus the said forces can overcome the mechanical ones acting upon thefibers, as e.g. inertia, natural fiber shrinkage, as well as uponaerodynamic forces caused by the high velocity of the fibers and theappurtenant components of the processing device, only with difficulties.The higher the spinning speed, the more unfavorable is the action of theinconsistency between the electrostatic forces and the mechanical forcesupon the degree of straightening and the evenness of the resulting yarn.It has been proved by experiments, that the fibers in the said devicesat rest, i.e. at that time at which the above mentioned mechanicalforces do not act but with the electrostatic field in action, arecorrectly straightened, this being substantially disturbed upon startingby the action of both mechanical and aerodynamic forces, as mentionedabove.

A further known method of spinning fibers consists in introducing fibersinto a rotary electrostatic field, in which said fibers are twisted. Thedisadvantage of this method consists in the small value of theelectrostatic forces in view of those required to exert a sufficienttwisting effect necessary for spinning fibers into a yarn of sufficientstrength.

A method of forming twisted yarn in which the spearated fibers aredeposited in a depositing zone on to a movable surface and are fed bymeans thereof into a withdrawing zone in which said fibers are twistedabout the axis of the yarn by frictional contact with a movable surfaceand a further reversing surface which closes or presses the fibers insaid withdrawing zone, respectively, is known. The auxiliary meansagainst retaining the fibers on the movable surface are formed either byan electrostatic field or by a sucking effect, said movable surfacebeing provided with perforations.

It is possible in that method to spin fibers at high speed, andparticularly to twist them by reversing frictional surfaces. However,there is a disadvantage which consists in that it is not possible toimpart a precise and constant twist to the yarn under operationalconditions. The twist variation and its unquaranteed degree within thenormal limits and practice substantially affects the strength of theyarn and a reduction of its quality and usefulness. This disadvantage isnot reduced even by simultaneously using twisting devices for falsetwist behind the frictional twisting device. Even that method isdisadvantageous in certain cases wherein the movable surface fortransferring fibers has defined zones for depositing and withdrawingfibers. This is the case particularly when, requiring high spinningspeed, which a considerable quantity of fibers is fed upon the twistingelement, such deposition on the movable surface being necessarily withthe fibers in separated condition.

Under such conditions, the limiting of the space for feeding fibers andfor depositing them on to the movable surface also entails a limiting ofthe output or a reduction of yarn quality, since for a suitabledepositing of fibers in straightened condition a shorter time isavailable in proportion to increased transporting speeds of the fibersin a limited space for feeding fibers and retaining them to the movablesurface. The defining of the fiber depositing zone makes it impossibleto feed fibers e.g. to the whole movable surface, to form new fibersequences there, or to perform thereon a more thorough blending and amore even fiber layer, e.g. by means of cyclic doubling. The method oftwisting yarn by frictional contact with a movable surface does not makeit possible to form these surfaces with a curved profile for the purposeof better adhesion of the fibers on the surface and thus achieving amore consequent straightening of the fibers between the poles for thepurpose of improving the properties of the produced yarn. It is alsodisadvantageous since twisting by frictional contact eliminates theapplication of doubling means, in which there is a free space betweenthe poles of the electrostatic field in which the fibers are retainedand fed in straightened condition to a twisting element by the effect ofsaid field, whereupon a simplification of the machine construction canbe achieved.

A further method of processing fibrous material is known, in which asliver of fibers is processed to yarn, said sliver being fed to atwisting element in opened condition, the separate fibers beingdeposited beside each other transversely to their longitudinal axis andbeing reversingly wrapped in the twisting zone and thereafter withdrawnin the form of yarn. The depositing of fibers and their arrangementbeside each other is performed on a conveying link, which is movabletransversely to the longitudinal axis of the fibers. The fibers aredeposited in straightened condition on to the conveying link in whichthey are secured by appurtenant retaining element in form of pins,needles, projections or similar elements.

The limitations and disadvantages of this method of producing yarnconsist namely in that the fibers deposited beside each other must besecured in straightened condition on a conveying link by mechanicalretaining means in the form of needles, pins, and similar elements. Thusthe passive resistance against twisting the sliver increases, and thewithdrawal of fibers from the conveying link upon wrapping issimultaneously made more difficult, said wrapping being made oppositelyfor that reason. Also the deposition of fibers on to the conveying linkand their arrangement and retaining beside each other in straightenedcondition by means of a depositing device is difficult and limited inits output. Therefore, it is necessary in certain cases to use for onetwisting element a plurality of depositing devices. The The depositionof fibers beside each other is also disadvantageous for certain casesfrom the viewpoint of the properties of the final product, i.e. theyarn, as through blending of fibrous material and the forming of newsequences of fibers of high evenness is not possible. With that method,it is impossible, e.g. to use the principle of cyclic redoubling ofseparated fibers, which secures a higher evenness of yarn due to morethorough blending of fibers from the separate parts of the fibrousmaterial.

The method of processing fibrous material to yarn according to thepresent invention has the purpose of reducing the above-mentioneddisadvantages and insufficiencies to a minimum by making possible ahigher velocity of processing fibrous material while simultaneouslyachieving a higher quality of the resulting product, i.e. yarn,according to the properties required.

In accordance with the method of processing fibrous material to yarnaccording to the present invention, the fibers being opened, and afterbeing opened are retained and made parallel on a doubling means by theaction of an electrostatic field and are continuously withdrawntherefrom by the rotating open yarn end, the rotation of which isperformed by a twisting means acting upon the yarn to be formed beyondthe section in which fibers are joined to the end of the yarn.

The device for performing the method according to the present inventionconsists particularly in that behind the fiber separating device for thefibrous material there is mounted a doubling means formed by the polesof a source of static electricity, the axis of rotation of the twistingmeans being directed toward one of said poles, said twisting meansacting upon the yarn behind the point ofjoining fibers to the yarn end.

Further features of the method and device according to the presentinvention are described in the following specification and are shown inthe accompanying drawings, in which:

FIG. 1 is a view in vertical section ofa first illustrative embodimentof the device for processing fibrous material into yarn according to thepresent invention;

FIG. 2 is a view in vertical section of a second embodiment of thedevice for processing fibrous material to yarn according to the presentinvention;

FIG. 3 is a schematic view in plan of the embodiment as shown in FIG. 2;

In the first embodiment shown in FIG. 1, the device according to thepresent invention is formed by a known device 1 for separating fibrousmaterial 20, the output 1' of device 1 being continued by a guiding tube2 with a widened end, of which the inlet part 2 is provided with apulley 3. The pulley 3 is embraced by a belt 4 transmitting theretorotary motion from a driving means (not shown), and distributing ribs 2"for imparting rotary motion to fibers l3 and forming a so-called cyclicdoubling of fibers on the circumference of poles or electrodes 7, 8.

Tube 2 is mounted rotatably in a frame 5, which surrounds space 4 of theelectrostatic field 6 formed by the two electrodes 7 and 8, suchelectrodes being connected to a source 9 of high voltage, and mounted ona rotary shaft 10, shaft 10 is provided on its lower end with a pulley11 which is embraced by belt 12 transmitting thereto a rotary motionfrom a driving means (not shown). The electrodes 7 and 8 have the shapeof bodies of revolution, and between their spaced confronting endsfibers 13 are straightened and deposited to sequences disposed abouttheir circumference. On the outer side of the end of electrode 8, atwisting element 14 is rotatably mounted at its immediate proximity inframe 5, said means being provided at its lower end with a pulley 15,which is in contact with a friction disc 16 imparting a rotary motion totwisting element 14 via pulley 161 and belt 162 driven from a drivingmeans which is not shown. The end of yarn 17 passes through twistingmeans 14, by means of which the ends of the fibers are withdrawn fromthe end of electrode 8 at a certain point to which the electrodes 7 and8 arrive during one revolution of the circumferential edge of electrode8. The withdrawn fibers 13 are wrapped on to the end of yarn I7 and aretwisted to yarn by a twist ing element. The finished yarn 17 iswithdrawn by a pair of withdrawing cylinders 18 and is wound onto abobbin 19 which is mounted, together with the withdrawing cylinders,apart from the frame 5 of the device. On frame 5 there may be situatedin the proximity of electrode 8, or twisting means 14, respectively,yarn diameter limiting means 600, e.g. a projection, a lug or a similarelement made either of non-conductive material, or also of conductivematerial. However, in the latter case an influence upon theelectrostatic field 6 cannot be excluded.

In the second embodiment, shown in FIGS. 2 and 3, the device accordingto the present invention is formed by a known drafting mechanism 21, ofwhich the first pair of rollers 210 feeds the fibrous material 20, thenext pair 2!] drafts it and the last pair 212 separates it. Below thedrafting mechanism 21, Le. below its last pair of rollers 2l2 there ismounted a device by means of which an electrostatic field 6 is formed.This device consists of two electrodes 7 and 8' connected to a source ofhigh voltage 9'. Electrodes 7' and 8' are mounted on a rotary shaft 10mounted in the machine frame 22, shaft 10' being provided at its lowerend and with a pulley ll, embraced belt 12, by means of which there istransmitted to shaft 10 a rotary motion from a driving means (notshown). Electrode 7' is formed in this case by a disc shaped plate, andpole 8' is formed by an outer ring which surrounds a non-conductiveplate 8' on the upper side of which the electrostatic field 6 issituated in the annulus between electrodes 7', 8'. Electrode 7' withcenter M (FlG. 3) may also be made in the fon'n of a cylindrical orconical projection coaxial to shaft 10, whereby an advantageous courseof the gradient of the electrostatic field, and thus higher efficiencyupon straightening fibers 13 is achieved. Also plate 8' may be of planarform, as shown in the drawing, or may also have another rotary shape ofarbitrary kind, e.g. a cone or a similar shape. Beside electrode 8'there is mounted at its immediate proximity a twisting means 14',through which there passes the end of yarn 17 by which are withdrawn ata certain point, through which pass during one revolution of electrodes7', 8 all points of the circumferential edge of electrode 8', the endsof fibers 13 on electrode 8' which are wrapped about the end of yarn l7and twisted by means of twisting means 14' to yarn 17. The twistingmeans 14' is given a rotary motion by means of a known device (notshown).

The yarn 17 is withdrawn from the twisting means 14' by a pair ofwithdrawing rollers 18 and is wound onto bobbin [9. The axis of thetwisting means 14 forms with fibers R3 in the electrostatic field 6 atthe point of their connection with the end of yarn 17 an angle alpha ofa value within the range from 0 to 80. The pole 8' which is situated atthe proximity of twisting means 14'. may advantageously be grounded, andthus twisting means 14 is not affected by the electrostatic field. Theangle alpha influences the direction of connecting fibers to therotating free yarn end. so that it is possible to change suitably theproperties of the yarn to be manufactured.

The device according to the present invention the third embodimentthereof shown in FIG. 4 consists of a known fiber separating device 1with an outlet 1' for opening fibrous material 20, which is directlyconnected to the space of electrostatic field 6", surrounded by ahousing 6a. Beside device 1 for opening fibrous material 20 there ismounted a vessel 30 which contains an adhesive agent. Inside vessel 30,there is mounted a pad roller 31 which is partially dipped into saidadhesive agent and is in permanent contact with a squeeze roller 32.Between vessel 30 and housing 60 of the space of electrostatic field 6'there is mounted a guiding roller 33. Thread 34, unwound from a winding(not shown) is guided between pad roller 3! and squeeze roller 32 andvia guiding roller 33 into inlet opening 61 of housing 60 of the spaceof electrostatic field 6', which is disposed beside outlet 1' of device1 for opening fibrous material 20 into the space of electrostatic field6'. The electrostatic field is formed by two electrodes 7b, 8!;connected to a high voltage source 9', to said electrodes 7b, 8b thereare fed fibers 13 from outlet 1' of the device I for opening fibrousmaterial 20. Poles 7b and 8b are made in the form of endless movabletapes driven from a drive source (not shown). in the space 6' of theelectrostatic field between poles 7b and 8b, fibers 13 are straightenedand guided in the direction of arrow 5 by movement of electrodes 7b and8b in the direction towards thread 34, by which they are withdrawn bythe common action of twist, adhesive agent, and the movement of saidthread in the direction of arrow R. Behind outlet 62 of housing 60 ofthe space 6' of the electrostatic field there is mounted a twistingmeans 14, through which thread 34 with fibers l3 wrapped therearoundpasses. The twisting means 14 is in contact with driving rollers 35provided at their ends with a pulley 36 embraced by belt 37, by means ofwhich a rotary motion is imparted to said twisting means via drivingrollers 35 from a driving source (not illustrated). In the twistingmeans 14 the fibers 13 are twisted around thread 34, whereby theresulting yarn 38 is formed, which is withdrawn by a pair of withdrawingrollers 18, the yarn 38 being wound onto bobbin 19.

The device according to the invention in the fourth embodiment as shownin FIG. 5 consists of a known device for opening and separating fibrousmaterial 20, which is continued by an outlet channel 1', opening into ahomogenizing space 60 for homogenizing the freely dispersed fibers 13 byretardation caused by the fact that the cross section of homogenizingspace 60 is at least five times larger than the cross section of outlet1' of separating device 1. The homogenizing space 60 may also beequipped with the nozzle 70, which is connected by a conduit 71 to asource of processing pressure fluid (not shown).

The opened lower part of the homogenizing space 60 is continued by aplate 80 of non-conductive material, at the circumference of which thereis located pole 8d and in its center electrode 7c, which are bothconnected to a high voltage source 9, thus forming and electrostaticfield 6c therebetween. Beside electrode Be a twisting means 140 issituated at the immediate proximity thereof, said twisting means 14cbeing imparted rotary motion by a known device (not shown) and yarn 17being passed therethrough which, by rotation imparted thereto bytwisting means 14c wraps fibers 13 assembled on plate 8c betweenelectrodes 7d and 80 about its end and the yarn 17 thus formed iswithdrawn by means of a pair of withdrawing rollers 18 and further woundonto bobbin 19. Shaft d, on which pole 7c with plate 8d are mounted, ismounted in frame 22 and is provided with a pulley ll, embraced by belt12, by which the rotary motion from a source (not shown) is transmittedto shaft 10d.

The device according to the present invention in the fifth embodimentshown in FIG. 6 consists of a feeding channel 1' connecting a known, notshown device for separating fibers, e.g. a carding machine with ahomogenizing space 60 for assembling separated fibers 13, in whichelectrodes 7f, 8f which are connected to a high voltage source 9, areguided longitudinally. Beside electrodes 8f there are mounted twistingmeans 14 in the immediate proximity thereof, a rotary motion beingimparted to twisting means 14e by a known device (not shown). Yarn 17passes through twisting means 14c, and wraps about its end fibers 13 byrotation thereof, said fibers being straightened between electrodes 7fand 8f, and is continuously withdrawn by pairs of withdrawing rollers 18and wound onto a not shown yarn winding.

Contrary to the devices as mentioned before, and as shown in FIGS. 1 to5, in which for each twisting means 14: there is used an independentdevice for separating fibers and an independent homogenizing space forprocessing the fibers by means of an electrostatic field, the embodimentas shown in FIG. 6 has a common homogenizing space 60 for a group oftwisting means 14c, as well as common electrodes 7f and 8f in the formof belts driven from a known source (not shown) and passing in thedirection of arrows S,S' longitudinally through homogenizing space 60,as well as a common device for separating the fibers and a commonfeeding chennel 1'.

In the proximity of the twisting means Me, in the direction of movementof electrodes 8e, there is mounted a sucking tube 63, which is connectedby a connecting channel 64 to a sucking channel 65, which is continuousalong the whole machine and is connected to a known underpressure(vacuum) source (not shown). Inside the connecting channel 64 there ismounted a closing element 68, e.g. a valve, a flap, a side valve etc.,which is controlled via a conduit 67 in a manner known from automationand control means from feeler 66 which senses from variations of yarntension, the breakage of yarn 17.

The devices according to the present invention perform the methodaccording to the present invention as follows:

ln the embodiment as shown in FIG. 1, the fibrous material 20 is fedinto the device 1 for opening fibers, in which the individual fibers 13are separated, said fibers passing through outlet 1' into the rotatingguiding tube 2, from which they slide down to the surface of ro tatingelectrode 7 and are fed into the space of electrostatic field 6 betweenthe two rotating electrodes 7, 8 between which fibers 13 are rearrangedand striaghtened in stationary condition by the action of the gradientof the electrostatic field.

By means of distributing ribs 2" fibers 13 are distributed about thecircumference of electrodes 7, 8, thus forming a new sequence by theso-called cyclic doubling of the separate elementary fiber layers, in amanner similar to that performed in a spinning chamber.

By the rotation of electrodes 7,8, fibers 13 are gradually fed to therotating twisting means 14, where the free yarn end 17 projectingtherefrom withdraws the fibers and wraps them around it and twists toyarn 17, which is thereupon withdrawn from twisting means 14 either at aconstant or a varying speed by means of withdrawing rollers 18 and woundonto bobbin 19, when frame 5 is provided with means 600, e.g. in theform of a projection, a lug or a similar part, this means acts upon theyarn end projecting from twisting means 14 to limit its diameter,whereby a better quality of produced yarn is achieved.

ln the embodiments as shown in FIGS. 2 and 3, the fibrous material 20 isat first drafted and separated by the appurtenant roller pairs 211, or212, respectively, of drafting mechanism 21, and fibers 13 made offibrous material 20 by separating are then brought into the space ofelectrostatic field 6 in which they are rearranged between electrodes 7'and mounted on a non-conductive plate 8' which rotates with a drivenshaft 10, and are straightened by the action of a gradient of theelectrostatic field 6. The direction of movement of fibers 13 from thepair of rollers 212 might be in the direction of shaft 10 or in adirection inclined to the length of said shaft, the theoretical point ofcontact of the fibers being either in the center M of electrode 7 or atan arbitrary distance therefrom on electrode 7' or on the non-conductiveplate 8'. Plate 8' may have a planar or a conical shape, or the shape ofany body of revolution. Fibers 13 in the electrostatic field arranged asmentioned above. are fed grudaully. by rotation of the electrodes 7', 8'to the twisting means 14 performing a rotary motion and are withdrawntherefrom by the free end of yarn l7 projecting therefrom and wrappedthereabout, and thereafter are twisted to the yarn inside the twistingmeans 14, said yarn being withdrawn either at a constant or a varyingspeed by withdrawing rollers 18 from the twisting means and thereafterbeing wound onto bobbin 19.

In the embodiment shown in FIG. 4, the fibrous material is fed to device1 for opening and separation, and therefrom the separated fibers l3 arefed through outlet 1' into the space of the electrostatic field 6' tothe electrodes 7b and 8b in the form of endless movable belts, wherethey are re-arranged due to the gradient of the electrostatic field 6'and straightened in stationary condition. Thread 34 is padded betweenthe padding roller 31 and the squeeze roller 32 with an adhesive agentfrom vessel 30 and are guided over guiding roller 33 through inlet 61into the space of electrostatic field 6, moving therein in the directionof arrow R. Fibers 13 which are straightened and rearranged betweenelectrodes 7b and 8b are brought to the thread 34 by their movement inthe direction of arrow S, and are wrapped in the twisting means by theaction of the adhesive agent, as well as by movement of the thread 34 inthe direction of arrow R by its twisting inside the rotating twistingmeans 14. In that manner, thread 34 ohtains the character of yarn coreand is changed to false twist yarn. Behind the twisting means 14, thistwist is anulled and on the surface of the yarn 38 thus formed thereremain fibers I3 withdrawn from the electrodes 7b, 8b of theelectrostatic field 6 adhered to and wrapped therearound. The resultingyarn 38 is withdrawn by means of withdrawing rollers 18 and are woundonto bobbin 19. In this method, the free end of yarn 17 is formed bystaple fibers and the twist thus formed on the yarn is true, while theyarn core is without twist.

In the embodiment as shown in FIG. 5, the fibrous material 20 is fedinto the device 1 for opening and separating fibers, and the separatefibers 13 pass therefrom through outlet 1' into the homogenizing space60, in which they are freely dispersed and retarded in that condition toat least one fifth of their speed at the outlet. The separating device 1thus making the flow of fibers 13 more even and forming a homogenousfiber blend. This effect can be supported by further means, eg nozzle70, from which a flow of pressure fluid fed through supply conduit 71from a not shown source causes an intensive turbulence insidehomogenizing space 60 and a blending of fibers coming to the proximityof poles 72, 8d against the fiber flow entering through outlet 1' intohomogenizing space 60. In this manner, an effect similar to theso-called cyclic doubling shown in FIG. I is achieved. The evenness ofthe fiber flow is better the larger is the homogenizing space 60. It issuitable, for the cross section of the homogenizing space 60 to be,relative to the cross section of outlet 1' from the separating device I,at least five times larger; a more intensive fiber blending may besecured by the use of the flow of pressure fluid from nozzle 70 into thehomogenizing space 60.

The fibers 13 are straightened by the effect of the electrostatic field6 between poles 72, 8d on conical plate 8e and continuously withdrawntherefrom by the rotating free end of yarn 17, to which a rotary motionis imparted by twisting means 14. The resulting yarn I7 is withdrawn bya pair of withdrawing rollers 18 and is wound onto bobbin 19. Theconicity of plate 8e may be of various values according to the need ofthe required technological conditions, and may have a value within therange from 0, in which case the plate is planar, as shown in FIGS. 2, 3,up to in which case an inner space of cylindrical shape is formed. Thesurface of plate 8e might be also suitably shaped for the purposed ofachieving a better straightening of the fibers upon piecing, e.g.curved, as shown in FIG. 6.

In the embodiment of FIG. 6, the fibrous material 20 which is opened andseparated by means of a not shown device, is fed through feeding channel1 into a homogenizing space 60, which is common for two or more twistingmeans 14, withdrawing means 18 and winding means 19 for the yarn. Thefeeding channel 1' may be in the form of a slot or a tube of continuouswidth, as shown in FIG. 6, or may be divided about its width intoseveral partial feeding channels 1' of eg circular cross section, whichopen into a common homogenizing space 60. The supplied fibers 13 may besubjected in the homogenizing space 60 to homogenization in a mannersimilar to that shown in FIG. 5, or by another known blending device,e.g. in a mechanical manner, by means of a rotating propeller inside thehomogenizing space 60. In view of the fact that the homogenizing space60 may have considerably larger dimensions than a homogenizing space forone separate twisting means, as shown in FIG. 5, a more intensiveblending of fibers 13 is achieved thereby as well as a better evennessof their flow to the exit, or their arrangement into a new sequencebetween the electrodes 7f, 8f, respectively.

The fibers 13 are in straightened condition, between electrodes 7f, 8]"continuously fed in the direction of arrows 8,8 to the separate twistingmeans 14, which are situated in the proximity of electrode 8f and impartrotation to the free end of yarn 17, onto which are wrapped the fedfibers 13, whereby yarn is formed, which is withdrawn by a pair ofwithdrawing rollers 18 and wound in a known manner and by a known deviceonto an arbitrary winding (not shown). The opening and separating devicemight be made either as a group device for a plurality of twisting means14 and withdrawing means 18, or a central device for the whole machine,or possibly also beside the machine as an independent device. Such anindependent opening and separating device is e.g. a carding machine,from which are pneumatically doffed the separated fibers 13, which aresubdued in the homogenizing space 60 of the device according to thepresent invention to uniforming and processed by cooperation of theelectrostatic field as specified above.

In FIG. 6, a device 68 for sucking ofi' fibers which are not spun intothe yarn, is diagrammatically shown. Such a device might be made also inall other alternative embodiments of the spinning device according tothe present invention, as eg in the embodiments as shown in FIGS. 1 to5. The operation of this device is in the embodiment in form of exampleas follows:

In the proximity of twisting means 14, is in the direction of movementof pole 8f there mounted a sucking device tube 63', for sucking offfibers 13 which have not been spun into yarn 17, particularly uponbreakage of yarn 17. These fibers are transported through connectingchannel 64 and further through sucking channel 65 into an accumulatingspace (not shown) mounted on the machine or apart therefrom. The suckingdevice 63 might be in action for the whole time of operation of themachine in all spinning heads, i.e. said device is neither switched offnor controlled by any means. In that case a smaller part of fibers 13which have not been spun in or not caught up by a free end of yarn 17 issucked off. For improvement of this device, and for saving power, it ispossible to open the connecting channels 64 only in the case when feeler66 emits the due signal by means of a transmitting member 67 to theclosing element in case breakage of yarn 17 occurs. Upon yarn breakage,the not spun fibers 13 are sucked off. As soon as the yarn is piecedagain, the closing element 68 closes the appurtenant connecting channel64.

The advantage of the method according to the present invention as wellas of the device for performing said method consists in that it ispossible to achieve by means thereof a controlled connection of thefiber to the yarn being formed. As the fiber are relatively at rest, itis possible to achieve their correct straightening, thus considerablymitigating the influence of mechanical and aerodynamical forces, whichwould unfavorably act upon staightening fibers during movement thereof.

A considerable advantage of the method of processing fibrous materialaccording to the present invention is the independent preliminarypreparation of fibers for being spum by means of electrostatic forces,apart from twisting. Thus it is possible to use on the one hand atwisting means, e.g. a spindle of small mass for twisting at high speedin the axis of the yarn independently from the electrostatic field, andparticularly it is possible to process to yarn fibers, which have beensubdued to opening and separation by an arbitrary means most suitablefor this purpose.

Thus, it is possible to make a group opening device for two or moretwisting means, or a central opening device common to the whole machinefrom which the fibers are transported in separated condition into theelectrostatic field and prepared therein for spinning in the separatespinning units. Thus, the construction of the machine can be simplifiedand the production costs reduced.

Fron the viewpoint of automation of the whole spinning technology, themethod according to the present invention makes it possible directly andcontinuously to connect an independent opening and separating device, ase.g. a carding machine to a spinning machine and to form thereby alreadyon the base of the known state of art a continuous spinning process.

A further advantage of the method according to the present inventionconsists in making it possible to spin yarn with a predetermined andconstant twist by using spindles with a safe gripping of the yarn.

The separate embodiments of the device for performing the methodaccording to the present invention, as mentioned above in thespecification, by no means cover the whole scope of the method of anddevice for performing the present invention. lt is possible to makestill further many modifications obvious to those skilled in the art andfalling within the scope of protection of the method according to thepresent invention.

What is claimed is:

l. A method of processing fibers to a yarn by cooperation of anelectrostatic field, comprising opening the fibers, retaining andparallelizing the opened fibers on a doubling means by the action of anelectrostatic field, and continuously withdrawing the parallelizedfibers from the doubling means at a zone in which the fibers areconnected to a rotating free end of yarn, the rotation of the free endof yarn being performed by a twisting means acting upon the yarn beingformed beyond the zone at which the fibers are connected to the rotatingfree end of yarn.

2. A method as claimed in claim 1, wherein the twisting means isseparate and apart from the means forming the electrostatic field.

3. A method as claimed in claim 1, wherein the para]- lelized andstraightened fibers are fed to the spinning point of the twisting meansin a direction transverse to the longitudinal axis of the fibers.

4. A method as claimed in claim 1, wherein the axis of the fibers isparallel to the axis of the yarn at the spinning point.

5. A method as claimed in claim 1, wherein the axis of the fibers formsan angle with respect to the axis of the yarn.

6. A method as claimed in claim 1, wherein the rotating free end of yarnis thrust into contact with the doubling means by the action ofelectrostatic forces.

7. A method as claimed in claim 1, comprising limiting the diameter ofthe rotating free end of the yarn by contacting it with a fixed yarnengaging means.

8. A method as claimed in claim 1, wherein the direction of rotation ofthe free end of yarn is parallel to the direction of movement of thedoubling means.

9. A method as claimed in claim 1, wherein the direction of rotation ofthe free end of yarn is opposite to the direction of movement of thedoubling means.

10. A method as claimed in claim 1, wherein the sequence of fibers onthe doubling means is different from the sequence of fibers in thefibrous material before its processing.

11. A method as claimed in claim 1, wherein the sequence of the fibersand the group situated on the doubling means is formed by randomdistribution of fibers on at least 30% of its surface.

12. A method as claimed in claim 1, wherein the sequence of fibers inthe group on the doubling means is formed according to a predeterminedprogram.

13. A method as claimed in claim 1, comprising passing the fibers afterthey have been separated through a homogenizing space, and increasingthe evenness of flow of the fibers before depositing them on thedoubling means by retarding their flow to at least one-fifth of theirspeed at the exit from the fiber separating device.

14. A method as claimed in claim 1, wherein the spinning of fibers fromthe electrostatic field is performed by fastening them to a continuousthread and subsequently twisting them around said thread.

15. Apparatus for processing fibers to yarn by cooperation of anelectric field comprising means for opening the fibers, means forretaining and parallelizing the opened fibers on a doubling means by theaction of an electrostatic field, and means for continuously withdrawingthe parallelized fibers from the doubling means, means for rotating thefree end of a yarn, said last named means including a twisting meansacting upon the yarn to be formed beyond the zone at which theparallelized fibers from the doubling means are connected to therotating end of yarn.

16. Apparatus as claimed in claim 15, wherein the doubling means ismounted beyond the fiber opening device and is formed by opposedelectrodes connected to a source of static electricity, and wherein theaxis of rotation of the twisting means acting upon the yarn beyond thezone of connecting the fibers to the free end of the yarn is directedtoward one of said electrodes.

17. Apparatus as claimed in claim 16, wherein said electrodes are formedby elements which are at least parts of bodies of revolution.

18. Apparatus as claimed in claim 16, wherein the electrodes comprise atleast portions of continuous belts.

19. Apparatus as claimed in claim 16, comprising a device for forming asequence of fibers according to a predetermined program disposed betweenthe fiber opening device and the electrostatic field.

20. Apparatus as claimed in claim 19, wherein the device for forming asequence of fibers according to a predetermined program is made in theform of a homogenizing space having a cross sectional area which is atleast five times greater than the cross sectional area of the exitpassage from the fiber separating device 21. Apparatus as claimed inclaim 20, comprising a nozzle opening into the homogenizing space forfeeding a processing fluid which homogenizes the flow of fibers throughsaid homogenizing space.

22. Apparatus comprising a plurality of processing units as defined inclaim 19, and wherein the homogenizing space is common to the twistingmeans of said plurality of processing units.

23. Apparatus as claimed in claim 16, wherein the axis of the twistingmeans forms an angle within the range from 0-80 with respect to thelongitudinal axis of the fibers at the point of spinning.

1. A method of processing fibers to a yarn by cooperation of an electrostatic field, comprising opening the fibers, retaining and parallelizing the opened fibers on a doubling means by the action of an electrostatic field, and continuously withdrawing the parallelized fibers from the doubling means at a zone in which the fibers are connected to a rotating free end of yarn, the rotation of the free end of yarn being performed by a twisting means acting upon the yarn being formed beyond the zone at which the fibers are connected to the rotating free end of yarn.
 2. A method as claimed in claim 1, wherein the twisting means is separate and apart from the means forming the electrostatic field.
 3. A method as claimed in claim 1, wherein the parallelized and straightened fibers are fed to the spinning point of the twisting means in a direction transverse to the longitudinal axis of the fibers.
 4. A method as claimed in claim 1, wherein the axis of the fibers is parallel to the axis of the yarn at the spinning point.
 5. A method as claimed in claim 1, wherein the axis of the fibers forms an angle with respect to the axis of the yarn.
 6. A method as claimed in claim 1, wherein the rotating free end of yarn is thrust into contact with the doubling means by the action of electrostatic forces.
 7. A method as claimed in claim 1, comprising limiting the diameter of the rotating free end of the yarn by contacting it with a fixed yarn engaging means.
 8. A method as claimed in claim 1, wherein the direction of rotation of the free end of yarn is parallel to the direction of movement of the doubling means.
 9. A method as claimed in claim 1, wherein the direction of rotation of the free end of yarn is opposite to the direction of movement of the doubling means.
 10. A method as claimed in claim 1, wherein the sequence of fibers on the doubling means is different from the sequence of fibers in the fibrous material before its processing.
 11. A method as claimed in claim 1, wherein the sequence of the fibers and the group situated on the doubling means is formed by random distribution of fibers on at least 30% of its surface.
 12. A method as claimed in claim 1, wherein the sequence of fibers in the group on the doubling means is formed according to a predetermined program.
 13. A method as claimed in claim 1, comprising passing the fibers after they have been separated through a homogenizing space, and increasing the evenness of flow of the fibers before depositing them on the doubling means by retarding their flow to at least one-fifth of their speed at the exit from the fiber separating device.
 14. A method as claimed in claim 1, wherein the spinning of fibers from the electrostatic field is performed by fastening them to a continuous thread and subsequently twisting them around said thread.
 15. Apparatus for processing fibers to yarn by cooperation of an electric field comprising means for opening the fibers, means for retaining and parallelizing the opened fibers on a doubling means by the action of an electrostatic field, and means for continuously withdrawing the parallelized fibers from the doubling means, means for rotating the free end of a yarn, said last named means including a twisting means acting upon the yarn to be formed beyond the zone at which the parallelized fibers from the doubling means are connected to the rotating end of yarn.
 16. Apparatus as claimed in claim 15, wherein the doubling means is mounted beyond the fiber opening device and is formed by opposed electrodes connected to a source of static electricity, and wherein the axis of rotation of the twistiNg means acting upon the yarn beyond the zone of connecting the fibers to the free end of the yarn is directed toward one of said electrodes.
 17. Apparatus as claimed in claim 16, wherein said electrodes are formed by elements which are at least parts of bodies of revolution.
 18. Apparatus as claimed in claim 16, wherein the electrodes comprise at least portions of continuous belts.
 19. Apparatus as claimed in claim 16, comprising a device for forming a sequence of fibers according to a predetermined program disposed between the fiber opening device and the electrostatic field.
 20. Apparatus as claimed in claim 19, wherein the device for forming a sequence of fibers according to a predetermined program is made in the form of a homogenizing space having a cross sectional area which is at least five times greater than the cross sectional area of the exit passage from the fiber separating device.
 21. Apparatus as claimed in claim 20, comprising a nozzle opening into the homogenizing space for feeding a processing fluid which homogenizes the flow of fibers through said homogenizing space.
 22. Apparatus comprising a plurality of processing units as defined in claim 19, and wherein the homogenizing space is common to the twisting means of said plurality of processing units.
 23. Apparatus as claimed in claim 16, wherein the axis of the twisting means forms an angle within the range from 0*-80* with respect to the longitudinal axis of the fibers at the point of spinning. 